News

The World's Oldest* Ice in Antarctica

Ice examined by EPICA scientists at Dome C is believed to be 530,000
years old. For several years they have been drilling through the Antarctic
Ice Sheet to obtain the longest possible continuous ice core record of
climate, and to understand how climate change works over several ice
age-interglacial climate cycles. The aim for the 2001-02 summer
season was to reach 2500 metres, and the final depth reached by the team of
eight drillers was 2864.22 metres (2.8 km). Eventually it is hoped to drill
down to a depth of 3.3 km (2 miles).

EPICA (European Project for Ice Coring in Antarctica) is a consortium of ten
European countries (Belgium, Denmark, France, Germany, Italy, Netherlands,
Norway, Sweden, Switzerland, UK). It is co-ordinated by the European
Science Foundation (ESF), and funded by the participating countries
and the European Union.

Dome Concordia (Dome C) is a broad topographic dome roughly centred at
75° 06’06 S, 123° 23’42 E on the polar plateau of East Antarctica (at
3233 m elevation above sea level), and is more than 700 km from the
coast. Average temperatures at the site are minus 44 degrees Celsius.

The EPICA research team is investigating the relationship between the
chemistry of the atmosphere and climate changes over the past 500,000 years,
especially the changes caused by carbon dioxide, methane and nitrous oxides.
The results will be used to test and enhance computer models used to predict
future climate. Earlier joint European studies of ice cores from Greenland
discovered several periods of very unstable climate in the past, which may
have implications for the climate of Europe if there is sustained
global warming in the future.

Dr. Eric Wolff, currently EPICA's chief scientist, who is based at the
British Antarctic Survey in Cambridge, UK, said that 1,400 metres of ice (roughly
9 tonnes of core) were processed in the field during the 2001-02 summer
season, with the UK's contribution being studies of the dielectric properties
of ice.

Note 1Beacon Valley, one of the dry valleys in East Antarctica has a
climate so arid that the land surface is ice free. However ice
lying beneath Miocene volcanic ash is believed to be a small remnant of a
glacier that Professor David Sugden of the University
of Edinburgh's Geography Department termed the 'oldest ice on Earth'.
Based upon the relationship of the Beacon Valley ice with radiometrically
dated volcanic ash, Sugden and his colleagues believe that it formed about
8 million years ago. However, contact relations of the ice and the
ash are not entirely clear and this interpretation has been challenged.
Some means of independently dating the ice is under investigatation.
See Earth and Planetary Science Letters, 2000, Vol.179, pp. 91-99.